Revenue (Summary of Disaggregation of Revenue by Product Line) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenues	$ 379.5	$ 403.4	$ 415.3	$ 420.1	$ 405.9	$ 414.3	$ 432.2	$ 405.7	$ 1,618.3	$ 1,658.1	$ 1,412.9
Supply Technologies Segment
Disaggregation of Revenue [Line Items]
Total revenues									611.5	636.8	561.8
Supply Technologies Segment | Supply Technologies
Disaggregation of Revenue [Line Items]
Total revenues									532.9	555.3
Supply Technologies Segment | Engineered specialty fasteners and other products
Disaggregation of Revenue [Line Items]
Total revenues									78.6	81.5
Assembly Components Segment
Disaggregation of Revenue [Line Items]
Total revenues									539.5	578.3	524.5
Assembly Components Segment | Fuel-related, rubber and plastic products
Disaggregation of Revenue [Line Items]
Total revenues									353.8	382.5
Assembly Components Segment | Aluminum products
Disaggregation of Revenue [Line Items]
Total revenues									185.7	195.8
Engineered Products Segment
Disaggregation of Revenue [Line Items]
Total revenues									467.3	443.0	$ 326.6
Engineered Products Segment | Industrial equipment
Disaggregation of Revenue [Line Items]
Total revenues									323.8	312.1
Engineered Products Segment | Forged and machined products
Disaggregation of Revenue [Line Items]
Total revenues									$ 143.5	$ 130.9